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(04:16:14 PM) otheruser@something.com: ?OTRv23? otheruser@something.com/Home has requested an Off-the-Record private conversation. However, you do not have a plugin to support that. See http://otr.cypherpunks.ca/ for more information.

You will have to follow some onscreen directions and coordinate with your buddy to exchange fingerprints.

Pick up that can citizen... The can of tyranny is thus kicked down the road another 50 yards with an illegal application of privacy.

To speed up step "9. Generate the key." you can yum install haveged which gives you more randomness so the key generation speeds up 100th times as fast! Otherwise that step can take several minutes
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rubo77Jul 8 at 17:01

You can create a new user on your first login, just create a Jabber "XMPP"-Account use a new username and one of the free jabber-domain of your choice (for example: "jabber.ccc.de") and check the box at the bottom in the registration page to crate that user now.

In your contactlist you have to activate the "Off-The-Record Messaging" Plugin under (german): "Werkzeuge"->"Erweiterungen". Activate it and click configure to enable logging of encrypted chat, if desired. (be aware that it is good manners to inform the other side in chat, that you enabled logging)